RDS active session timeout popup?

Does anyone know of a tool that will give you a pop up message that tells the users that they have are about to reach their active session time limit.

We have a GPO in place that limits active session to 12 hours

Solution 1:

The scripting language of your choice and task scheduler (at logon), group policy, or the startup programs group? Something like this, perhaps:

[System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms")
Start-Sleep -s 43140
[System.Windows.Forms.MessageBox]::Show("Sessions are limited to twelve hours.  You will be logged off in one minute.  Please save your work.")